Northboro, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.4 °F (low) to 62 °F (high). Annual precipitation averages 35.4 Inches. Northboro is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 13.6 °F | 33.0 °F | 0.82 in. |
| February | 18.1 °F | 38.4 °F | 1.12 in. |
| March | 28.5 °F | 51.2 °F | 1.96 in. |
| April | 39.1 °F | 63.0 °F | 3.37 in. |
| May | 51.3 °F | 73.1 °F | 5.58 in. |
| June | 61.7 °F | 82.2 °F | 5.23 in. |
| July | 65.7 °F | 85.8 °F | 4.48 in. |
| August | 63.0 °F | 84.3 °F | 3.71 in. |
| September | 53.6 °F | 78.2 °F | 3.21 in. |
| October | 41.5 °F | 66.1 °F | 2.8 in. |
| November | 29.2 °F | 50.4 °F | 1.86 in. |
| December | 19.3 °F | 37.8 °F | 1.29 in. |
| Annual | 40.4 °F | 62 °F | 35.43 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |